Participate with other selected investigators leading to the implementation of a controlled clinical trial as described in the Protocol and Manual of Operations. The trial involves the screening of defined populations to identify men aged 35-54 at the highest 10% of risk for developing coronary heart disease and establishment of the intervention modalities for the reduction of cholesterol by diet, by blood pressure reduction by antihypertensive drugs, and by reduction of cigarette smoking, as described more fully in standard protocol (as amended) attached to and made a part of this contract. Establish a core staff for undertaking the planned intervention protocol with training of such staff in the conduct of responsibilities outlined in the protocol. Establish necessary community relations with local physicians and the populations to be screened for planned recruitment of 600 eligible participants with a risk fraction classification in the upper 10% for CHD.